Add terminal hook defined_color_hook

* src/termhooks.h (defined_color_hook): New terminal hook.

* src/xterm.c:
* src/nsterm.m:
* src/term.c:
* src/w32term.c: Set defined_color_hook.

* src/nsterm.m (ns_defined_color_hook): New hook wrapper procedure.

* src/xfaces.c: Use defined_color_hook.
(defined_color): Remove.

* src/image.c (image_defined_color): New wrapper procedure for NS.
Remove redefinitions of x_defined_color, and rename x_defined_color to
image_defined_color.

12 files changed, 87 insertions, 65 deletions

diff --git a/src/dispextern.h b/src/dispextern.h
index 6c1cdf3e2d3..4d6d0371d38 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -3413,6 +3413,9 @@ void x_free_colors (struct frame *, unsigned long *, int);
 
 void update_face_from_frame_parameter (struct frame *, Lisp_Object,
                                        Lisp_Object);
+extern bool tty_defined_color (struct frame *f, const char *, XColor *, bool,
+                               bool);
+
 Lisp_Object tty_color_name (struct frame *, int);
 void clear_face_cache (bool);
 unsigned long load_color (struct frame *, struct face *, Lisp_Object,
diff --git a/src/image.c b/src/image.c
index 47e86436912..e3b7873f0a4 100644
--- a/src/image.c
+++ b/src/image.c
@@ -89,8 +89,6 @@ typedef struct w32_bitmap_record Bitmap_Record;
 #define PIX_MASK_RETAIN	0
 #define PIX_MASK_DRAW	1
 
-#define x_defined_color w32_defined_color
-
 #endif /* HAVE_NTGUI */
 
 #ifdef HAVE_NS
@@ -101,8 +99,6 @@ typedef struct ns_bitmap_record Bitmap_Record;
 
 #define PIX_MASK_RETAIN	0
 
-#define x_defined_color(f, name, color_def, alloc) \
-  ns_defined_color (f, name, color_def, alloc, 0)
 #endif /* HAVE_NS */
 
 #if (defined HAVE_X_WINDOWS \
@@ -1424,7 +1420,11 @@ image_alloc_image_color (struct frame *f, struct image *img,
 
   eassert (STRINGP (color_name));
 
-  if (x_defined_color (f, SSDATA (color_name), &color, 1)
+  if (FRAME_TERMINAL (f)->defined_color_hook (f,
+                                              SSDATA (color_name),
+                                              &color,
+                                              true,
+                                              false)
       && img->ncolors < min (min (PTRDIFF_MAX, SIZE_MAX) / sizeof *img->colors,
 			     INT_MAX))
     {
@@ -4470,8 +4470,8 @@ xpm_load_image (struct frame *f,
 	    {
 	      if (xstrcasecmp (SSDATA (XCDR (specified_color)), "None") == 0)
 		color_val = Qt;
-	      else if (x_defined_color (f, SSDATA (XCDR (specified_color)),
-					&cdef, 0))
+	      else if (FRAME_TERMINAL (f)->defined_color_hook
+                       (f, SSDATA (XCDR (specified_color)), &cdef, false, false))
 		color_val = make_fixnum (cdef.pixel);
 	    }
 	}
@@ -4479,7 +4479,8 @@ xpm_load_image (struct frame *f,
 	{
 	  if (xstrcasecmp (max_color, "None") == 0)
 	    color_val = Qt;
-	  else if (x_defined_color (f, max_color, &cdef, 0))
+	  else if (FRAME_TERMINAL (f)->defined_color_hook
+                   (f, max_color, &cdef, false, false))
 	    color_val = make_fixnum (cdef.pixel);
 	}
       if (!NILP (color_val))
@@ -5685,7 +5686,11 @@ pbm_load (struct frame *f, struct image *img)
 #ifdef USE_CAIRO
       if (! fmt[PBM_FOREGROUND].count
           || ! STRINGP (fmt[PBM_FOREGROUND].value)
-          || ! x_defined_color (f, SSDATA (fmt[PBM_FOREGROUND].value), &xfg, 0))
+          || ! FRAME_TERMINAL (f)->defined_color_hook (f,
+                                                       SSDATA (fmt[PBM_FOREGROUND].value),
+                                                       &xfg,
+                                                       false,
+                                                       false))
         {
           xfg.pixel = fg;
           x_query_colors (f, &xfg, 1);
@@ -5694,7 +5699,11 @@ pbm_load (struct frame *f, struct image *img)
 
       if (! fmt[PBM_BACKGROUND].count
           || ! STRINGP (fmt[PBM_BACKGROUND].value)
-          || ! x_defined_color (f, SSDATA (fmt[PBM_BACKGROUND].value), &xbg, 0))
+          || ! FRAME_TERMINAL (f)->defined_color_hook (f,
+                                                       SSDATA (fmt[PBM_BACKGROUND].value),
+                                                       &xbg,
+                                                       false,
+                                                       false))
 	{
           xbg.pixel = bg;
           x_query_colors (f, &xbg, 1);
@@ -6353,7 +6362,11 @@ png_load_body (struct frame *f, struct image *img, struct png_load_context *c)
 	 current frame background, ignoring any default background
 	 color set by the image.  */
       if (STRINGP (specified_bg)
-	  ? x_defined_color (f, SSDATA (specified_bg), &color, false)
+	  ? FRAME_TERMINAL (f)->defined_color_hook (f,
+                                                    SSDATA (specified_bg),
+                                                    &color,
+                                                    false,
+                                                    false)
 	  : (image_query_frame_background_color (f, &color), true))
 	/* The user specified `:background', use that.  */
 	{
@@ -8038,7 +8051,8 @@ gif_load (struct frame *f, struct image *img)
   if (STRINGP (specified_bg))
     {
       XColor color;
-      if (x_defined_color (f, SSDATA (specified_bg), &color, 0))
+      if (FRAME_TERMINAL (f)->defined_color_hook
+          (f, SSDATA (specified_bg), &color, false, false))
         {
           uint32_t *dataptr = data32;
           int r = color.red/256;
@@ -8799,7 +8813,11 @@ imagemagick_load_image (struct frame *f, struct image *img,
 
     specified_bg = image_spec_value (img->spec, QCbackground, NULL);
     if (!STRINGP (specified_bg)
-	|| !x_defined_color (f, SSDATA (specified_bg), &bgcolor, 0))
+	|| !FRAME_TERMINAL (f)->defined_color_hook (f,
+                                                    SSDATA (specified_bg),
+                                                    &bgcolor,
+                                                    false,
+                                                    false))
       image_query_frame_background_color (f, &bgcolor);
 
     bg_wand = NewPixelWand ();
@@ -9534,7 +9552,11 @@ svg_load_image (struct frame *f, struct image *img, char *contents,
     XColor background;
     Lisp_Object specified_bg = image_spec_value (img->spec, QCbackground, NULL);
     if (!STRINGP (specified_bg)
-	|| !x_defined_color (f, SSDATA (specified_bg), &background, 0))
+	|| !FRAME_TERMINAL (f)->defined_color_hook (f,
+                                                    SSDATA (specified_bg),
+                                                    &background,
+                                                    false,
+                                                    false))
       image_query_frame_background_color (f, &background);
 
     /* SVG pixmaps specify transparency in the last byte, so right
diff --git a/src/nsterm.m b/src/nsterm.m
index fa43b6a32cf..88c16b68ecf 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -5232,6 +5232,7 @@ ns_create_terminal (struct ns_display_info *dpyinfo)
   terminal->update_end_hook = ns_update_end;
   terminal->read_socket_hook = ns_read_socket;
   terminal->frame_up_to_date_hook = ns_frame_up_to_date;
+  terminal->defined_color_hook = ns_defined_color;
   terminal->mouse_position_hook = ns_mouse_position;
   terminal->get_focus_frame = ns_get_focus_frame;
   terminal->focus_frame_hook = ns_focus_frame;
diff --git a/src/term.c b/src/term.c
index a492276c888..a150da7084b 100644
--- a/src/term.c
+++ b/src/term.c
@@ -3839,6 +3839,7 @@ clear_tty_hooks (struct terminal *terminal)
   terminal->update_begin_hook = 0;
   terminal->update_end_hook = 0;
   terminal->set_terminal_window_hook = 0;
+  terminal->defined_color_hook = 0;
   terminal->mouse_position_hook = 0;
   terminal->frame_rehighlight_hook = 0;
   terminal->frame_raise_lower_hook = 0;
@@ -3882,6 +3883,7 @@ set_tty_hooks (struct terminal *terminal)
   terminal->menu_show_hook = &tty_menu_show;
 #endif
   terminal->set_terminal_window_hook = &tty_set_terminal_window;
+  terminal->defined_color_hook = &tty_defined_color; /* xfaces.c */
   terminal->read_socket_hook = &tty_read_avail_input; /* keyboard.c */
   terminal->delete_frame_hook = &tty_free_frame_resources;
   terminal->delete_terminal_hook = &delete_tty;
diff --git a/src/termhooks.h b/src/termhooks.h
index 29c5737ee15..8852be9c29b 100644
--- a/src/termhooks.h
+++ b/src/termhooks.h
@@ -24,6 +24,7 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 /* Miscellanea.   */
 
 #include "lisp.h"
+#include "dispextern.h"
 #include "systime.h" /* for Time */
 
 struct glyph;
@@ -488,6 +489,17 @@ struct terminal
   void (*update_end_hook) (struct frame *);
   void (*set_terminal_window_hook) (struct frame *, int);
 
+  /* Decide if color named COLOR_NAME is valid for the display
+   associated with the frame F; if so, return the RGB values in
+   COLOR_DEF.  If ALLOC (and MAKEINDEX for NS), allocate a new
+   colormap cell.
+
+   If MAKEINDEX (on NS), set COLOR_DEF pixel to ARGB.  */
+  bool (*defined_color_hook) (struct frame *f, const char *color_name,
+                              XColor *color_def,
+                              bool alloc,
+                              bool makeIndex);
+
   /* Multi-frame and mouse support hooks.  */
 
   /* Return the current position of the mouse.
diff --git a/src/w32fns.c b/src/w32fns.c
index 350f8d3f975..df37326c109 100644
--- a/src/w32fns.c
+++ b/src/w32fns.c
@@ -1173,7 +1173,7 @@ gamma_correct (struct frame *f, COLORREF *color)
 
 int
 w32_defined_color (struct frame *f, const char *color, XColor *color_def,
-		   bool alloc_p)
+		   bool alloc_p, bool _makeIndex)
 {
   register Lisp_Object tem;
   COLORREF w32_color_ref;
@@ -1260,7 +1260,7 @@ w32_decode_color (struct frame *f, Lisp_Object arg, int def)
 
   /* w32_defined_color is responsible for coping with failures
      by looking for a near-miss.  */
-  if (w32_defined_color (f, SSDATA (arg), &cdef, true))
+  if (w32_defined_color (f, SSDATA (arg), &cdef, true, false))
     return cdef.pixel;
 
   /* defined_color failed; return an ultimate default.  */
@@ -6103,7 +6103,7 @@ DEFUN ("xw-color-defined-p", Fxw_color_defined_p, Sxw_color_defined_p, 1, 2, 0,
 
   CHECK_STRING (color);
 
-  if (w32_defined_color (f, SSDATA (color), &foo, false))
+  if (w32_defined_color (f, SSDATA (color), &foo, false, false))
     return Qt;
   else
     return Qnil;
@@ -6118,7 +6118,7 @@ DEFUN ("xw-color-values", Fxw_color_values, Sxw_color_values, 1, 2, 0,
 
   CHECK_STRING (color);
 
-  if (w32_defined_color (f, SSDATA (color), &foo, false))
+  if (w32_defined_color (f, SSDATA (color), &foo, false, false))
     return list3i ((GetRValue (foo.pixel) << 8) | GetRValue (foo.pixel),
 		   (GetGValue (foo.pixel) << 8) | GetGValue (foo.pixel),
 		   (GetBValue (foo.pixel) << 8) | GetBValue (foo.pixel));
diff --git a/src/w32term.c b/src/w32term.c
index 9e51ddf6429..9560d27a124 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -7159,6 +7159,7 @@ w32_create_terminal (struct w32_display_info *dpyinfo)
   terminal->update_end_hook = w32_update_end;
   terminal->read_socket_hook = w32_read_socket;
   terminal->frame_up_to_date_hook = w32_frame_up_to_date;
+  terminal->defined_color_hook = w32_defined_color;
   terminal->mouse_position_hook = w32_mouse_position;
   terminal->get_focus_frame = w32_get_focus_frame;
   terminal->focus_frame_hook = w32_focus_frame;
@@ -7261,8 +7262,8 @@ w32_term_init (Lisp_Object display_name, char *xrm_option, char *resource_name)
   /* initialize palette with white and black */
   {
     XColor color;
-    w32_defined_color (0, "white", &color, 1);
-    w32_defined_color (0, "black", &color, 1);
+    w32_defined_color (0, "white", &color, true, false);
+    w32_defined_color (0, "black", &color, true, false);
   }
 
 #ifdef WINDOWSNT
diff --git a/src/w32term.h b/src/w32term.h
index d742aea5c20..a0ba19014bc 100644
--- a/src/w32term.h
+++ b/src/w32term.h
@@ -243,7 +243,7 @@ struct w32_display_info *x_display_info_for_name (Lisp_Object);
 extern struct w32_display_info *w32_term_init (Lisp_Object,
 					       char *, char *);
 extern int w32_defined_color (struct frame *f, const char *color,
-                              XColor *color_def, bool alloc_p);
+                              XColor *color_def, bool alloc_p, bool _makeIndex);
 extern int w32_display_pixel_height (struct w32_display_info *);
 extern int w32_display_pixel_width (struct w32_display_info *);
 extern void initialize_frame_menubar (struct frame *);
diff --git a/src/xfaces.c b/src/xfaces.c
index 3f627d3843d..e6aba0747d0 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -898,11 +898,11 @@ tty_lookup_color (struct frame *f, Lisp_Object color, XColor *tty_color,
     return false;
 }
 
-/* A version of defined_color for non-X frames.  */
+/* An implementation of defined_color_hook for tty frames.  */
 
-static bool
+bool
 tty_defined_color (struct frame *f, const char *color_name,
-		   XColor *color_def, bool alloc)
+		   XColor *color_def, bool alloc, bool _makeIndex)
 {
   bool status = true;
 
@@ -929,36 +929,6 @@ tty_defined_color (struct frame *f, const char *color_name,
   return status;
 }
 
-
-/* Decide if color named COLOR_NAME is valid for the display
-   associated with the frame F; if so, return the rgb values in
-   COLOR_DEF.  If ALLOC, allocate a new colormap cell.
-
-   This does the right thing for any type of frame.  */
-
-static bool
-defined_color (struct frame *f, const char *color_name, XColor *color_def,
-	       bool alloc)
-{
-  if (!FRAME_WINDOW_P (f))
-    return tty_defined_color (f, color_name, color_def, alloc);
-#ifdef HAVE_X_WINDOWS
-  else if (FRAME_X_P (f))
-    return x_defined_color (f, color_name, color_def, alloc);
-#endif
-#ifdef HAVE_NTGUI
-  else if (FRAME_W32_P (f))
-    return w32_defined_color (f, color_name, color_def, alloc);
-#endif
-#ifdef HAVE_NS
-  else if (FRAME_NS_P (f))
-    return ns_defined_color (f, color_name, color_def, alloc, true);
-#endif
-  else
-    emacs_abort ();
-}
-
-
 /* Given the index IDX of a tty color on frame F, return its name, a
    Lisp string.  */
 
@@ -1003,7 +973,8 @@ face_color_gray_p (struct frame *f, const char *color_name)
   XColor color;
   bool gray_p;
 
-  if (defined_color (f, color_name, &color, false))
+  if (FRAME_TERMINAL (f)->defined_color_hook
+      (f, color_name, &color, false, true))
     gray_p = (/* Any color sufficiently close to black counts as gray.  */
 	      (color.red < 5000 && color.green < 5000 && color.blue < 5000)
 	      ||
@@ -1043,7 +1014,7 @@ face_color_supported_p (struct frame *f, const char *color_name,
 	   && face_color_gray_p (f, color_name)))
     :
 #endif
-    tty_defined_color (f, color_name, &not_used, false);
+    tty_defined_color (f, color_name, &not_used, false, false);
 }
 
 
@@ -1087,9 +1058,10 @@ load_color2 (struct frame *f, struct face *face, Lisp_Object name,
 	   || target_index == LFACE_STRIKE_THROUGH_INDEX
 	   || target_index == LFACE_BOX_INDEX);
 
-  /* if the color map is full, defined_color will return a best match
+  /* if the color map is full, defined_color_hook will return a best match
      to the values in an existing cell. */
-  if (!defined_color (f, SSDATA (name), color, true))
+  if (!FRAME_TERMINAL (f)->defined_color_hook
+      (f, SSDATA (name), color, true, true))
     {
       add_to_log ("Unable to load color \"%s\"", name);
 
@@ -4243,11 +4215,19 @@ two lists of the form (RED GREEN BLUE) aforementioned. */)
 
   if (!(CONSP (color1) && parse_rgb_list (color1, &cdef1))
       && !(STRINGP (color1)
-	   && defined_color (f, SSDATA (color1), &cdef1, false)))
+           && FRAME_TERMINAL (f)->defined_color_hook (f,
+                                                      SSDATA (color1),
+                                                      &cdef1,
+                                                      false,
+                                                      true)))
     signal_error ("Invalid color", color1);
   if (!(CONSP (color2) && parse_rgb_list (color2, &cdef2))
       && !(STRINGP (color2)
-	   && defined_color (f, SSDATA (color2), &cdef2, false)))
+           && FRAME_TERMINAL (f)->defined_color_hook (f,
+                                                      SSDATA (color2),
+                                                      &cdef2,
+                                                      false,
+                                                      true)))
     signal_error ("Invalid color", color2);
 
   if (NILP (metric))
diff --git a/src/xfns.c b/src/xfns.c
index b21d1689a5c..1e96f577328 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -653,7 +653,7 @@ gamma_correct (struct frame *f, XColor *color)
 
 bool
 x_defined_color (struct frame *f, const char *color_name,
-		 XColor *color, bool alloc_p)
+		 XColor *color, bool alloc_p, bool _makeIndex)
 {
   bool success_p = false;
   Colormap cmap = FRAME_X_COLORMAP (f);
@@ -698,7 +698,7 @@ x_decode_color (struct frame *f, Lisp_Object color_name, int mono_color)
 
   /* x_defined_color is responsible for coping with failures
      by looking for a near-miss.  */
-  if (x_defined_color (f, SSDATA (color_name), &cdef, true))
+  if (x_defined_color (f, SSDATA (color_name), &cdef, true, false))
     return cdef.pixel;
 
   signal_error ("Undefined color", color_name);
@@ -4110,7 +4110,7 @@ DEFUN ("xw-color-defined-p", Fxw_color_defined_p, Sxw_color_defined_p, 1, 2, 0,
 
   CHECK_STRING (color);
 
-  if (x_defined_color (f, SSDATA (color), &foo, false))
+  if (x_defined_color (f, SSDATA (color), &foo, false, false))
     return Qt;
   else
     return Qnil;
@@ -4126,7 +4126,7 @@ DEFUN ("xw-color-values", Fxw_color_values, Sxw_color_values, 1, 2, 0,
 
   CHECK_STRING (color);
 
-  if (x_defined_color (f, SSDATA (color), &foo, false))
+  if (x_defined_color (f, SSDATA (color), &foo, false, false))
     return list3i (foo.red, foo.green, foo.blue);
   else
     return Qnil;
diff --git a/src/xterm.c b/src/xterm.c
index 82be9b28d0e..951f71cedda 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -13296,6 +13296,7 @@ x_create_terminal (struct x_display_info *dpyinfo)
   terminal->read_socket_hook = XTread_socket;
   terminal->frame_up_to_date_hook = XTframe_up_to_date;
   terminal->buffer_flipping_unblocked_hook = XTbuffer_flipping_unblocked_hook;
+  terminal->defined_color_hook = x_defined_color;
   terminal->mouse_position_hook = XTmouse_position;
   terminal->get_focus_frame = x_get_focus_frame;
   terminal->focus_frame_hook = x_focus_frame;
diff --git a/src/xterm.h b/src/xterm.h
index 637ff2fd502..84a478dbd2c 100644
--- a/src/xterm.h
+++ b/src/xterm.h
@@ -1251,7 +1251,7 @@ extern void destroy_frame_xic (struct frame *);
 extern void xic_set_preeditarea (struct window *, int, int);
 extern void xic_set_statusarea (struct frame *);
 extern void xic_set_xfontset (struct frame *, const char *);
-extern bool x_defined_color (struct frame *, const char *, XColor *, bool);
+extern bool x_defined_color (struct frame *, const char *, XColor *, bool, bool);
 #ifdef HAVE_X_I18N
 extern void free_frame_xic (struct frame *);
 # if defined HAVE_X_WINDOWS && defined USE_X_TOOLKIT